Petrillo in U.S. Pat. No. 4,168,267 discloses that various phosphinylalkanoyl substituted prolines are useful as hypotensive agents due to their ability to inhibit the angiotensin converting enzyme.
Ondetti, et al. in U.S. Pat. No. 4,151,172 discloses that various phosphonoacyl prolines are useful as hypotensive agents due to their ability to inhibit the angiotensin converting enzyme.
Mercaptoacyl derivatives of proline and substituted prolines are known to be useful hypotensive agents due to their angiotensin converting enzyme inhibition activity. Ondetti, et al. in U.S. Pat. No. 4,105,776 disclose such compounds wherein the proline ring is unsubstituted or substituted by an alkyl or hydroxy group. Ondetti, et al. in U.S. Pat. No. 4,154,935 disclose such compounds wherein the proline ring is substituted with one or more halogens. Ondetti, et al. in U.S. Pat. No. 4,316,906 disclose such compounds wherein the proline ring is substituted by various ethers and thioethers. Krapcho in U.S. Pat. No. 4,217,359 disclose such compounds wherein the proline ring has a carbamoyloxy substituent. Krapcho in U.S. Pat. No. 4,311,697 discloses compounds wherein the proline ring has a diether, dithioether, ketal or thioketal substituent in the 4-position. Krapcho in U.S. Pat. No. 4,316,905 discloses such compounds wherein the proline ring has a cycloalkyl, phenyl, or phenyl-lower alkylene substituent. Ondetti, et al. in U.S. Pat. No. 4,234,489 disclose such compounds wherein the proline has a keto substituent in the 5-position. Krapcho, et al. in U.S. Ser. No. 162,341 filed June 23, 1980 now U.S. Pat. No. 4,310,461 disclose such compounds wherein the proline has an imido, amido, or amino substituent in the 4-position. Iwao, et al. in U.K. patent application No. 2,027,025 disclose such compounds wherein the proline has an aromatic substituent in the 5-position.
Mercaptoacyl derivatives of 3,4-dehydroproline are disclosed as angiotensin converting enzyme inhibitors by Ondetti in U.S. Pat. No. 4,129,566. Mercaptoacyl serivatives of thiazolidinecarboxylic acid and substituted thiazolidinecarboxylic acid are disclosed as angiotensin converting enzyme inhibitors by Ondetti in U.S. Pat. No. 4,192,878 and by Yoshitomo Pharmaceutical Ind. in Belgian Pat. No. 868,532.
Tanabe in European Patent Application No. 18,549 disclose angiotensin converting enzyme inhibitors having a carboxyethylcarbamoyl group attached to the N-atom of tetrahydroisoquinoline carboxylic acid and this same sidechain coupled to the N-atom of proline in Japanese Application No. 5151-555.
Thorsett, et al. in European Patent Application Ser. No. 9,183 disclose phosphoryl derivatives of aminoacids including proline. These compounds are disclosed as being hypotensive agents due to their angiotensin converting enzyme inhibition activity.